base/threading/thread_checker_impl.h

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef BASE_THREADING_THREAD_CHECKER_IMPL_H_
   6 #define BASE_THREADING_THREAD_CHECKER_IMPL_H_
   7
   8 #include "base/base_export.h"
   9 #include "base/synchronization/lock.h"
  10 #include "base/threading/platform_thread.h"
  11
  12 namespace base {
  13
  14 // Real implementation of ThreadChecker, for use in debug mode, or
  15 // for temporary use in release mode (e.g. to CHECK on a threading issue
  16 // seen only in the wild).
  17 //
  18 // Note: You should almost always use the ThreadChecker class to get the
  19 // right version for your build configuration.
  20 class BASE_EXPORT ThreadCheckerImpl {
  21  public:
  22   ThreadCheckerImpl();
  23   ~ThreadCheckerImpl();
  24
  25   bool CalledOnValidThread() const;
  26
  27   // Changes the thread that is checked for in CalledOnValidThread.  This may
  28   // be useful when an object may be created on one thread and then used
  29   // exclusively on another thread.
  30   void DetachFromThread();
  31
  32  private:
  33   void EnsureThreadIdAssigned() const;
  34
  35   mutable base::Lock lock_;
  36   // This is mutable so that CalledOnValidThread can set it.
  37   // It's guarded by |lock_|.
  38   mutable PlatformThreadId valid_thread_id_;
  39 };
  40
  41 }  // namespace base
  42
  43 #endif  // BASE_THREADING_THREAD_CHECKER_IMPL_H_